This allows nationals from one European Union (EU) country to live and work in another.

But it is full of loopholes that allow governments to deny some EU migrants benefits and public services. And it brutally represses immigration from outside the EU.

The single market sought to do on a bigger scale what nation states did to help capitalism

Creating a single market was a defining goal of European integration.

It would do on a bigger scale what nation states had done to help capitalism grow. A nation state with uniform laws, taxes and infrastructure meant capitalists faced few barriers in exploiting any opportunity they saw to make profit. This could be combined with restrictions on foreign competitors.

The state ruled to make market forces sovereign. But by the Cold War, competition between national markets in Europe paled before their common rivalry with other power blocs.

Demolishing the protectionist tariffs and regulations that each state used to promote its own capitalists was a big gamble for Europe’s rulers.

It took until 1993 to successfully launch the single market Its rules are still unevenly applied by governments with one eye on their national markets and nationalist politics.